I am new but am dealing with the same kind of issue (mine is due to canibalism). I learned the hard way, I lost one of my hens this week and a couple of weeks ago due to not removing them from the pen in time. The other chickens took advantage of the weakness, picked their bottoms clean, took skin and feathers. Big bloody mess, they both ended up dead. I just went out this morning and found several others were taking feathers off each others bottoms again, so I took some BYC advise and put blue kote and pine tar on everyones bottoms, hurt or not (because of canibal problems). They did peck at it but wiped their beaks due to not liking the pine tar taste. (I do not know if Blue Kote alone will stop others from pecking at the wound) Will see tomorrow if it was enough. Be sure to check for lice and mites while you are doing this, she would need to be dusted if she has them. I found the pine tar and blue kote in the horse section of our local feed supply store. Good Luck and keep looking for the cause of the trouble in the first place. This advise is just to prevent further damage to the area. There is a LOT of info on this site!!
